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The conjecture that every cubic polyhedral graph is Hamiltonian. It was proposed by Tait in 1880 and refuted by Tutte (1946) with the counterexample on 46 vertices (Lederberg 1965) now known as Tutte's graph. Had the conjecture been true, it would have implied the four-color theorem.
The following table summarizes some named counterexamples, illustrated above. The smallest examples known has 38 vertices (Lederberg 1965), and was apparently also discovered by D. Barnette and J. Bosák around the same time.
graph | reference | |
38 | Barnette-Bośak-Lederberg graph | Lederberg (1965), Thomassen (1981), Grünbaum (2003, Fig. 17.1.5) |
42 | Faulkner-Younger graph 42 | Faulkner and Younger (1974) |
42 | Grinberg graph 42 | Faulkner and Younger (1974) |
44 | Faulkner-Younger graph 44 | Faulkner and Younger (1974) |
44 | Grinberg graph 44 | Sachs (1968), Berge (1973), Read and Wilson (1998, p. 274) |
46 | Grinberg graph 46 | Bondy and Murty (1976, p. 162) |
46 | Tutte's graph | Tutte (1972), Bondy and Murty (1976, p. 161) |
94 | Thomassen graph 94 | Thomassen (1981) |
124 | 124-Grünbaum graph 124 | Zamfirescu (1976) |
Berge, C. Graphs and Hypergraphs. New York: Elsevier, 1973.Bondy, J. A. and Murty, U. S. R. Fig. 9.27 in Graph Theory with Applications. New York: North Holland, 1976.
Faulkner, G. B. and Younger, D. H. "Non-Hamiltonian Cubic Planar Maps." Discr. Math. 7, 67-74, 1974.
Grünbaum, B. Fig. 17.1.5 in Convex Polytopes, 2nd ed. New York: Springer-Verlag, 2003.
Honsberger, R. Mathematical Gems I. Washington, DC: Math. Assoc. Amer., pp. 82-89, 1973.
Lederberg, J. "DENDRAL-64: A System for Computer Construction, Enumeration and Notation of Organic Molecules as Tree Structures and Cyclic Graphs. Part II. Topology of Cyclic Graphs." Interim Report to the National Aeronautics and Space Administration. Grant NsG 81-60. December 15, 1965.
http://profiles.nlm.nih.gov/BB/A/B/I/U/_/bbabiu.pdf.Pegg, E. Jr. "The Icosian Game, Revisited." Mathematica J. 310-314, 11, 2009.
Read, R. C. and Wilson, R. J. An Atlas of Graphs. Oxford, England: Oxford University Press, pp. 263 and 274, 1998.
Sachs, H. "Ein von Kozyrev und Grinberg angegebener nicht-Hamiltonischer kubischer planarer Graph." In Beiträge zur Graphentheorie. pp. 127-130, 1968.
Skiena, S. Implementing Discrete Mathematics: Combinatorics and Graph Theory with Mathematica. Reading, MA: Addison-Wesley, p. 198, 1990.
Tait, P. G. "Remarks on the Colouring of Maps." Proc. Royal Soc. Edinburgh 10, 729, 1880.
Thomassen, C. "Planar Cubic Hypohamiltonian and Hypotraceable Graphs." J. Comb. Th. B 30, 36-44, 1981.
Tutte, W. T. "On Hamiltonian Circuits." J. London Math. Soc. 21, 98-101, 1946.Tutte, W. T. "Non-Hamiltonian Planar Maps." In Graph Theory and Computing (Ed. R. Read). New York: Academic Press, pp. 295-301, 1972.
Zamfirescu, T. "On Longest Paths and Circuits in Graphs." Math. Scand. 38, 211-239, 1976.
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دراسة يابانية لتقليل مخاطر أمراض المواليد منخفضي الوزن
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اكتشاف أكبر مرجان في العالم قبالة سواحل جزر سليمان
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اتحاد كليات الطب الملكية البريطانية يشيد بالمستوى العلمي لطلبة جامعة العميد وبيئتها التعليمية
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